# How can we get lightship weight from inclining experiment

Discussion in 'Stability' started by Aqib Jahangir Amio, Oct 13, 2018.

1. Joined: Oct 2018
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Location: Dhaka

### Aqib Jahangir AmioNew Member

We know, Metacentric height GM=(w x d)/((tangent (angle) x displacement))

My question is that, from where do we get the lightship displacement?? Is it from initial stability booklet or from somewhere else?

2. Joined: Sep 2011
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Location: Spain

### TANSLSenior Member

I deduce that you already have the weight of the boat at the time of doing the inclining test. You only have to deduct the weights that are not part of the light ship, that were on board at that moment, and add the weights that, not being on board at that moment, are part of the light ship. Simple, add, subtract and multiply.
But the best thing you can do is read the technical texts about it, study a little more, do not look for shortcuts and, if you're not clear about it, ask your teachers, who are the ones who should teach you

3. Joined: Nov 2012
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Location: Delta BC

### JSLSenior Member

what size of boat is it????
If the stability book is current (you will have to do a lightship survey) you may be able to use it. If not, another method..-->
If boat is small , get it weighed. On a trailer over highway scales (not the most accurate) or get some scales. The largest I have been involved with was 85 feet (24m) and some house movers (who I have used many times before) came in and weighed the boat and also gave me the LCG and TCG. Procedure was done in about 3 hours.

4. Joined: Sep 2011
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Location: Spain

### TANSLSenior Member

Apparently what the OP wants to know is how to "get lightship weight from inclining experiment", that is, from the inclining experiment, not through other methods.

5. Joined: Nov 2012
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Location: Delta BC

### JSLSenior Member

You are correct but the 'topic' and his first post don't quite match up unless he meant 'for' instead of 'from'.... which I assumed.
How can we get lightship weight from inclining experiment

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